Last month, Unite local government staff members voted by 73% in a similar ballot to reject the pay deal and, of these, 88% backed industrial action.

GMB members have also voted against the deal in a consultative ballot and are now moving to vote on strike action.

All three unions recommended members reject the pay offer, arguing council staff are being offered less than teachers, and are calling for pay parity across the local government workforce.

Cosla said the offer of a 3% increase for those earning up to £80,000 puts staff on a par with those working in the NHS and other parts of the public sector, and warned any further increase would lead to cuts to jobs and services.

Unison’s Johanna Baxter said: “What this result demonstrates is a real anger and frustration amongst Unison members at the lack of action by Cosla and the Scottish Government to address the serious issue of low pay in local government.

“Unison will talk to other local government trade unions on Friday to discuss further action and we will inform employers of the ballot results then.

“As the Scottish Government prepare their budget we will put further pressure on them to make more money available to fund a decent pay rise for local government staff.”

She said the next step is holding a statutory ballot on industrial action.

Cosla resources spokeswoman Gail Macgregor expressed her “disappointment at the outcome of the ballot”.

She said: “We value our workforce and our 3% offer matches other offers within the public sector in Scotland. However, whilst disappointed, we as employers look forward to discussing this with Unison at our joint meeting tomorrow.”

A Scottish Government spokesman said: “We value and recognise the contribution of all local authority staff. However, pay for local government employees, other than teachers, is negotiated between the unions and Cosla, and the Scottish Government is not part of that process.”